From 06720e2a8dcf986af8ba8f14098afd2af6d0b4b8 Mon Sep 17 00:00:00 2001
From: Bernhard Miklautz <bmiklautz@thinstuff.com>
Date: Wed, 26 Sep 2012 15:45:30 +0200
Subject: [PATCH] build: check libavcodec api version

If pkg-config is available libavcodec api version is checked and
cmake fails if the required version isn't available.

In case pkg-config isn't available a notification message with the
required version is printed.

This fixes/prevents #740.
---
 cmake/FindFFmpeg.cmake | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/cmake/FindFFmpeg.cmake b/cmake/FindFFmpeg.cmake
index add7336ed..3151be906 100644
--- a/cmake/FindFFmpeg.cmake
+++ b/cmake/FindFFmpeg.cmake
@@ -5,6 +5,9 @@
 #  FFMPEG_INCLUDE_DIRS  - combined include directories
 #  FFMPEG_LIBRARIES    - combined libraries to link
 
+set(REQUIRED_AVCODEC_VERSION 0.8)
+set(REQUIRED_AVCODEC_API_VERSION 53.25.0)
+
 include(FindPkgConfig)
 
 if (PKG_CONFIG_FOUND)
@@ -31,6 +34,14 @@ endif()
 
 FIND_PACKAGE_HANDLE_STANDARD_ARGS(FFmpeg DEFAULT_MSG AVUTIL_FOUND AVCODEC_FOUND)
 
+if (AVCODEC_VERSION)
+	if (${AVCODEC_VERSION} VERSION_LESS ${REQUIRED_AVCODEC_API_VERSION})
+		message(FATAL_ERROR "libavcodec version >= ${REQUIRED_AVCODEC_VERSION} (API >= ${REQUIRED_AVCODEC_API_VERSION}) is required")
+	endif()
+else()
+		message("Note: To build libavcodec version >= ${REQUIRED_AVCODEC_VERSION} (API >= ${REQUIRED_AVCODEC_API_VERSION}) is required")
+endif()
+
 if(FFMPEG_FOUND)
 	set(FFMPEG_INCLUDE_DIRS ${AVCODEC_INCLUDE_DIR} ${AVUTIL_INCLUDE_DIR})
 	set(FFMPEG_LIBRARIES ${AVCODEC_LIBRARY} ${AVUTIL_LIBRARY})